1. Field of the Invention
This invention relates to a single-axis coarse and fine adjustment device in which coarse and fine adjustments can be accomplished by a single guide mechanism and which is additionally provided with novel drive means called a medium adjustment.
2. Description of the Prior Art
For use with microscopes, there are various types of coarse adjustment handle (in a single-axis coarse adjustment or coarse and fine adjustment device). One of them is such that the stroke of the stage for one complete rotation of the coarse adjustment handle is of the order of 3 to 6 mm. This type is suitable to effect the focusing of objective lenses having low magnifications ranging from 4x to 10x. On the other hand, however, such coarse adjustment handle is unsuitable in that it must be frequently rotated to lower the stage when interchange of the cover glass is desired or when the end of the objective lens is to be immersed in oil. Further, it is insensitive to the focusing of objective lenses having an extremely low magnification such as 1x. Such coarse adjustment system is most often found in the microscopes produced in Europe.
There are also coarse adjustment handles designed such that the stroke of the stage for one complete rotation of the coarse adjustment handle is of the order of 20 to 40 mm. This overcomes the disadvantages peculiar to the above-described system. In other words, it is suitable for interchange of the cover glass or for the oil-immersing operation. Nevertheless, because of the great stroke, it is unsuitable for the focusing of objective lenses having magnifications or 4x to 10x. In order to effect such focusing by fine adjustment, the fine adjustment handle must be many times rotated and this is cumbersome in use. Such coarse adjustment system is most often found in the microscopes produced in Japan.